From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: [PATCH 01/18] Make TSC offset writes non-preemptible
Date: Sun, 18 Jul 2010 17:30:38 +0300
Message-ID: <4C43100E.20707@redhat.com>
References: <1278987938-23873-1-git-send-email-zamsden@redhat.com> <1278987938-23873-2-git-send-email-zamsden@redhat.com>
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Cc: KVM <kvm@vger.kernel.org>, Marcelo Tosatti <mtosatti@redhat.com>,
	Glauber Costa <glommer@redhat.com>,
	Linux-kernel <linux-kernel@vger.kernel.org>
To: Zachary Amsden <zamsden@redhat.com>
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On 07/13/2010 05:25 AM, Zachary Amsden wrote:
>
> +void guest_write_tsc(struct kvm_vcpu *vcpu, u64 data)
> +{
> +	struct kvm *kvm = vcpu->kvm;
> +	u64 offset;
> +
> +	spin_lock(&kvm->arch.tsc_write_lock);
>    

Perhaps spin_lock_irq() for even more accuracy?

spin_lock_irq_nmi_smi_hypervisor(), if you can find it.

> +	offset = data - native_read_tsc();
> +	kvm_x86_ops->write_tsc_offset(vcpu, offset);
> +	spin_unlock(&kvm->arch.tsc_write_lock);
> +
> +	/* Reset of TSC must disable overshoot protection below */
> +	vcpu->arch.hv_clock.tsc_timestamp = 0;
> +}
> +EXPORT_SYMBOL_GPL(guest_write_tsc);
> +
>    


-- 
error compiling committee.c: too many arguments to function